A standard food chopper as described in German patent 885,467 of Muller comprises a housing having side walls and a generally semicylindrical floor formed with holes and having an inner surface generally centered on a horizontal axis, a shaft journaled in the side walls at the axis for rotation about the axis, respective elongated elements spaced axially apart along the axis, extending radially of the axis, and each having an inner end fixed at the axis and an outer end fixed in the floor, and a plurality of cutter blades spaced axially along the shaft, fixed thereto, and extending radially therefrom. Thus the shaft can be rotated to orbit the cutter blades and thereby chop material against the elongated elements, which may be fixed blades. The material is chopped finer and finer until the bits can pass through the perforated floor.
Other such choppers disclosed, for example, in German patent 107,295 of Sichel, German patent 162,584 of Brunner, or German patent 183,155 of Schwetz, work similarly. All have the tendency to clog or to recirculate the material being chopped until it is mushy. Most need to be meticulously emptied and cleaned, even in the middle of chopping, for instance, a pile of onions, since material clogs the perforated floor or outlet plate.